Huang Longjun

(Baise SHUANGTIAN International Minerals Pty Co．LTD,Baise,Guangxi 531501)

Abstract:With the rapid development of society,people"s demand for natural energy is increasing.Coal resource is one kind of non-renewable resources,which is a flammable organic rock,formed by luxuriant plants in the appropriate geological environment that buried in the sand then gradually accumulated into a thick layer long ago,and subjected to prolonged natural coalification.Coal mines are divided into open-pit coal mines and open-pit coal mines.The miner needs the aid of aerial passenger device when going down to mine,due to the large slope and the long distance of the roadway,the passenger will lift the seat up and down in the middle of the roadway,at the same time,the floor heave of the roadway will be deformed to different degreesand other influencing factors,which is likely to lead to theaccident that the seat fallsoff therope after passing the supporting wheel in the operation of the aerial passenger device,which is a serious threat to the safety of passengers.In this paper,the improvement measures of anti-dropping rope of aerial passenger device are studied to improve the operation efficiency and safety level of overhead device and promote the orderly progressof underground coal minetransportation.

Keywords:aerial passenger device;rope-proof protection device;improvement measure

In the underground transportation equipment of coal mine,the fixed rope-holding-riding device(commonly known as monkey car)is the special tools for transporting the workers in inclined shaft of coal mine.The aerial passenger device has the advantages of reliable operation,simple operation,convenient operation,small power consumption,convenient maintenance and high conveying efficiency.However,due to the coal mine roadway is too long and the bending degree is large,the beam of aerial passenger device often appears the phenomenon of extrusion deformation,which leads to the running Angle of the wire rope between the support rope wheel and overhead device becoming larger, and the frequent occurrence of the phenomenon of rope breaking in practical use,which brings hidden dangers to the personal safety of workers and staff.Combined with the current situation of our unit,the anti-dropping rope protection device of the aerial passenger device is designed to strengthen the rope catching function of the aerial passenger device and improve the safety level of the employees"aerial passenger device.

I.Working Principle of Aerial Passenger Device in Coal Mine

The steel wire rope in the aerial passenger device of coal mine is installed on the driving wheel,the pressure rope wheel,the supporting rope wheel and the tail wheel.After being tightened by the weight hammer tensioning device,the power output of the driving device will drive the steel wire rope and the driving wheel to run in an infinite cycle.The steel wire rope and the cable hanger on the passenger device will mechanically self-lock during operation,and the cable hanger will lock on the steel wire rope and go up or down during operation to complete the purpose of conveying workers[1].The electric machine on the drive device output power to drive the reducer wire rope and drive wheel to do cycle operation without pole,lifting chair is locked on the running wire rope to do up and down movement with the wire rope,to achieve the purpose of transporting miners.The datum center line of roadway elevation shall be tested before installing the beam of aerial passenger device,which shall be taken as the datum of installation.According to the drawings,the designers shall pre-embed the beam,supporting wheel beam,tail wheel,guide rail beam and hammer beam of the driving part,and the installed pressure rope wheel and supporting rope wheel shall be in the same line with the entire Central Line on one side,with the deviation value of±2mm[2].

After a long period of operation,the diameter and length of the wire rope of the aerial vehicle device will become smaller.Therefore,in the daily work of maintenance personnel to regularly adjust the tension device and cable hanger clamping force,and so that the height of the hammer has been maintained suspended state.Because after a period of operation of the wire rope ropeway,the driving wheel and the liner of the tail wheel will wear to about 10mm.If it is not replaced immediately,it is easy to cause the jumping and swinging phenomenon of the rope hanger and the hanging chair when they pass the ropeway.In serious cases,the rope will drop,which threatens the personal safety of passengers.

II.Cause of Aerial Passenger Device for Wire Rope Dropping

Aerial passenger device brings a lot of convenience to miners and improves the efficiency of underground transportation and mining.Aerial passenger device not only promotes the construction of intrinsically safe coal mine,but also reduces the labor intensity of miners.Increasing the application of aerial passenger device in coal mine work can improve the economic benefits of coal mining enterprises. However, many frequent safety accidents have brought great impact on the lives of coal mine workers.The reasons leading to safety accidents are not only the collision injury caused by the shaking of the aerial passenger device or the flying accident caused by the aerial passenger device,but alsothefollowingreasons.

(i)The Wire Rope Jumpsat the Joints oints

The wire ropes used in the aerial vehicle devices are poleless wire ropes.Using a butt joint allows the wire rope to form a circle in a poleless state.The technology of wire rope butt lap is not up to standard,the rope core diameter at the knot is not the same.According to the Coal Mine Safety Regulations,the splicing length of the steel wire rope shall not be less than 1000 times of the diameter of the steel wire rope.But there are more than 20 kinds of wire ropes for the aerial vehicle,and the length of the connection is about 30 meters.The diameter of the rope core is different,in the running through the rope wheel will have a jump,and when the amplitude of jump is too large,the wire rope will out of the wheel groove.

(ii)The Height of the Rope Wheel is Not is Not Consistent stent

The aerial passenger device will operate in the roadway going up and down the mountain.The narrow length of the roadway results in that some of the trolley wheels are not in the same horizontal line when the trolley is installed,and the height of the rope supporting wheels is inconsistent.Too high or too low of the supporting rope wheel will cause the wire rope to fall off when passing by,and the steel wire rope and the supporting rope wheel will be derailed,leadingtothepath dropping[3].

(iii)The Lining of the Holding Rope Wheel is eel is Badly Worn y Worn

After running for a long time,the wheel lining is easy to wear.The wheel liner of the supporting rope wheel increases the personal threat of the passengersafter fatiguewear.

(iv)The Slingis Broken roken

Some wire ropes run abnormally and fall off due to deformation or damage of the moorings in the aerial vehicles.Or the cable hanger is damaged and turns over to the inside of the wire rope.When the wire rope runs to the pulley,it is blocked by the pulley,and the wire rope falls out of the pulley groove under the impact of elastic force,causing safety accidents[4].

(v)Human Factors ctors

The personnel involved in the mining work are basically local miners who have not received safety training and there are many accidents caused by human factors in the operation of the overhead vehicle.For example,if the passenger sits in an improper posture and puts his feet on the stirrups of the hanging chair,it will easily lead to the shaking of the wire rope and the situation of dropping.When passengers are on and off the hanging chair,if the action amplitude is too large,the position of the hanging chair will be moved,bringing safety risks to the person who wants to hang the chair behind.Maintenance personnel did not do a good job in daily equipment maintenance and testing work,can not find the safety hidden trouble of aerial passenger devicein time,causingthewireropetofall.

III.Rope-proof Protection Measures of the Aerial Passenger Device

In order to reduce the safety accident rate of aerial passenger devices,coal mining enterprises have adopted the rope-proof protection measures in the application of aerial passenger devices.According to the above various security issues to improve research,develop reasonable solutions.A series of preparations should be made before the safety trip rope protection device.The installation team shall fix the crossbeam of the aerial passenger device and complete the basic work.The mine party shall determine the position of the middle line and the waist line of the roadway,mark on the beam,and install the anti-dropping rope protection device in strict accordance with the middle line and the waist line.

(i)Install Rope-proof Device evice

The optimum design of the rope-proof device for the overhead passenger is carried out,it is firmly fixed on the supporting rope wheel,and the processing material of the anti-dropping rope protection device is the common auxiliary material.The protection device shall be provided with safety devices such as head and tail offside protection,wire rope life limit protection,lower limit position protection device of weight hammer,emergency stop protection,up and down slope rope dropping protection device,voice prompt upon arrival,rope breaking protection and so on.When installing the anti-dropping device,the construction personnel shall install the steel wire rope on the inside of the supporting rope wheel to prevent the steel wire rope from dropping during the operation[5].The inner side of the rope path of the anti-dropping protection device can be made into an arc with a diameter of 12mm,so as to reduce the abrasion caused by the supporting rope wheel to the wire rope during operation and expand the width of the wire rope operating range.The baffle plate is connected and fixed with the pin shaft,and the pin shaft itself has a spring,which ensures that the seat retainer of the aerial passenger device can be quickly reset when passing through,and the anti-dropping device can always play a protective role.There is a column pin with casing on the outside of the rope supporting wheel,which can drive the steel wire rope to rotate to achieve the purpose of preventing the rope from falling off without affecting the normal rotation of the rope supporting wheel of the aerial passenger device[6].

(ii)Do a Good Job of Inserting the Rope End of End of the Wire Rope e Rope

When replacing or installing the wire rope,carefully wrap the inserted rope head with recycled cloth,wrap each rope head about 1 meter,insert and connect the forward running joint according to the running direction of the wire rope,and slowly pull the original rope core,pay attention not to exert too much force,to avoid pulling the rope core directly.After inserting the rope head that needs to be inserted into the inner part of the wire rope,cut off the original rope core,and then hit the wire rope with a rubber hammer to combine the original rope core with the new rope core to complete the work of inserting the wire rope head,ensuring that it will not jump in operation.

(iii)Underspeed Skid Protection Device evice

The skidding of the wire rope on the supporting pulley will increase the friction between the wire rope and the wheel groove,resulting in serious wear and tear of the wire rope.The previous content has described the influence of the quality of the wire rope on the operation safety of the aerial passenger device.When the wire rope is seriously damaged,it will lead to the unstable operation of the cable hanger and the safety accident of sliding rail or falling rope.In view of this problem,the staff can use the high sensitivity and high precision hall sensor PLC acquisition pulse signal,analyze and calculate the pulse data.When the operating speed of the aerial passenger device is more than 20%different from that of the rope pulley,the power supply will be cut off automatically.After 3 seconds,the safety brake will realize under-speed skid protection.

(iv)Anti-everse Protection ction

The negative force of the device will increase and result in the reverse movement.The pulse data are collected by the bipolar high precision hall sensor,analyze the pulses,determine the direction of the cable car.When the aerial passenger device is 200mm backward,the power supply will be automatically cut off by PLC control,and the working brake will be started to realize anti-reverse protection.

(v)Perform Routine Maintenance nance

Regular maintenances on the aerial passenger devices should be carried out,and both the advance-inspection and after-maintenance should be done as well.Some mechanical parts may become worn-out and loose after the aerial passenger device has been in operation for some time.In order to ensure that the equipment can give full play to its performance and ensure the safety and reliability of the equipment,relevant departments need to regularly inspect the equipment and timely repair and replace worn parts when problems are found.They also need to carry out a comprehensive inspection every three months,and check the loose parts every day,and make a good record.

IV.Conclusion

Over 4,200 sets of aerial passenger devices have been used in more than 2,000 mines in China,and an average of 400,000 miners ride aerial passenger devices up and down every day.It is an important matter in the safety management of coal mine enterprises to ensure the personal safety of workers in the process of collecting and transporting coal mine work.At present,the commonly used antidropping protection device is mainly to prevent the wire rope from grooving.When the wire rope is about to leave the wheel groove,the possible path will be closed to avoid the wire rope in the stuck or self-twisting under the premise of the occurrence of the grooving phenomenon,improve the safety coefficient of the aerial passenger device,to ensure the safety of passengers,and promote the safe and orderly operation of coal mine transport work.In daily work,more training should be given to the staff who take the aerial passenger device.The first-time passengers need to understand the operation characteristics of the aerial passenger device,master the ride plan,start from themselves to implement the safe and civilized ride,reduce the risk of the aerial passenger device and reduce the possibility of safety accidents.